Shopping bag having reinforced walls

ABSTRACT

A collapsible shopping bag having four sides and a square bottom when opened out from a flattened state. It is formed by two layers of flexible and heat-sealing plastics foil with an intermediate stiffening sheet of Kraft paper inserted between such layers extending continuously across the bottom and along two opposite bag sides. The bag in flattened state has two sideforming walls connected by a transverse bellows fold to form the square bottom and the mating longitudinal edges of the walls and the ends of the bellows fold are closed by heat sealing of the plastic foil layers.

D United States Patent [111 3,568,918

[72] Inventor Karl 0101 Blomqvist 2,815,898 12/1957 Thompson 229/55l-lackstavagen 7, S-184 Akersberga, 2,821,337 1/ 1958 Morgan, Jr. 229/57Sweden 3,067,926 12/1962 Brady 229/55 [211 App]. No. 796,492 3,396,9018/1968 McFedries, Jr.. 229/55 [22] Filed Feb. 4, 1969 3,468,470 9/1969Sengewald 229/55X Patented Mar. 9, 1971 FOREIGN PATENTS [32] PriorityFeb. 9,1968, Oct. 11, 1968 [33] Switzerland 1 1,069,268 5/1967 GreatBritain 229/57 [31 1735/1968 and 13772/1968 Primary Examiner-Raphael H.Schwartz Attorney-Wenderoth, Lind & Ponaclc [54] SHOPPING BAG HAVINGREINFORCED WALLS 1 Claim, 2 Drawing Figs. I [52] US. Cl 229/55,ABSTRACT: A collapsible shopping bag having four sides and 150/1-7, /12229/54 a square bottom when opened out from a flattened state. it is[51] r 33/02 formed by two layers of flexible and heat-sealing plasticsfoil 365d 33/10 with an intermediate stiffening sheet of Kraft paperinserted Fleld of Search 229/55, 54, between such layers extendingcontinuously across the bottom 57,58 53; 12 and along two oppositebagsides. The bag in flattened state has two side-forming wallsconnected by a transverse bellows [56] References (med fold to form thesquare bottom and the mating longitudinal UNITED STATES PATENTS edges ofthe walls and the ends of the bellows fold are closed 2,766,926 10/1956Thompson 229/55 by heat sealing of the plastic foil layers.

ATENTED m 9197:

KARL OLOF BLOMQVIST,

Inventor By, u.)mllmym Attorneyfl 1 SHOPPING BAG HAVING REINFORCED WALLSBACKGROUND OF THE INVENTION of plastics have also come into use. Plasticbags can easily be given a strength sufficient tostand a load of about20 kg., but it is an inconvenience that they are difficult to open fromflattened state. Further, such bags are not self-supporting, andtherefore one person must sometimes hold up the bag, while anotherperson puts in the goods.

SUMMARY OF THE INVENTION According to the invention, said drawbacks areeliminated by a bag made of double layers of soft and heat-sealingplastic foils with at least one intermediate stiffening sheet of Kraft.paper or plastics extending continuously across the bottom and alongtwo opposite sides of the bag. The double layers of plastic foils donot, per se, involve an improvement, as the desired strength can also beobtained by a single sheet if a foil material of sufficient thickness isselected; but their purpose is to enclose the stiffening sheet and holdit in place without it being necessary to secure said paper sheet by atroublesome gluing operation. As known, a Kraft paper sheet may berather stiff but yet it maintains the property of being readilyfoldable, so that the flattening of the stiffened bag is not made moredifficult. Another advantage is that-the bag will have a pleasantappearance in that its interior has a uniform and smooth surface.

When the flattened bag is opened and its bottom is unfolded, saidstiffening sheet imparts to the bag a rigidity sufficient to make thebag self-supporting in the same way as an opened paper bag. Two or moresheets of paper may be used, but as a rule it is sufficient with onesingle layer of Kraft paper having weight of 60-100 g./sq.m., forinstance. Preferably, the stiffening sheet covers the whole bottom andthe two sides of the bag. V A

Owing to the fact that said stiffening sheet does not extend into theend walls of the bag, the bag may be flattened as readily as aconventional plastic bag. When folding the foils into the shape of abag, the edges of the foils may in the known way be permitted to meet inthe end walls of the bag outside the edges of the stiffening sheet whichthus does not prevent a normal heat sealing.

The shopping bag may to advantage be of the type which -in flattenedstate consists of two parallel walls connected by a transverse bellowsfold adapted to form the bottom, the matin g longitudinal edge of saidsidewalls as well as the ends of the bellows fold being closed by heatsealing.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described inmore detail with reference to the accompanying drawings, in which:

FIG. 1 shows a perspective view of a flattened shopping bag, the bottomof which is half unfolded for better clarity;

FIG. 2 shows a perspective view of the same bag in opened condition.

a sufficient rigidity to stand by DETAILED DESCRIPTION or THE PREFERREDEMBODIMENTS In producing the bag shown in FIGS. 1 and 2, two plasticfoils (3 and 4 in FIG. 2,) are placed on either side of an intermediateKraft paper sheet 5, the width of which corresponds to the length of thesquare bottom to be produced. The plastic foils which are wider than thepaper sheet, have edge portions 6 and 7 projecting outside thelongitudinal edges 8 and 9 (FIG. 1) of the paper to form the end wallsof the bag. The laminate thus obtained is folded double in forrmrzgtransverse bellows fold 10 adapted to serve as bottom. The epth of saidbellows fold 10 is equal to the width of each edge portion 6 and 7,respectively.

The mating edges 11,12 of the foils brought together by the followingoperation are heat sealed throughout their length so that the bellowsfold is transformed into a pocket closed at both ends. Preferably theouter foil 3 is dimensioned to project slightly outside the transverseedges of the paper sheet 5 and of the inner foil-4 at the open end ofthe bag, and these projecting portions are folded back and cemented tothe inside of the inner foil 4, as shown at 13 in FIG. 2.

. In the known way, handles may be made integral with the bag-formingfoils if the latter have sufficient strength, but if the foils are madethin it may be more convenient to make handle members of a strongerplastic material and attach them to the bag by heat sealing. ln FIGS. 1and 2, two rectangular pieces 14 of plastic foilhave been folded doubleand applied such that their. legs straddle the edge portions of the bagwalls at the open end of the bag. One of the handle legs has been heatsealed to the outside of theouter foil 3 (at 15) and the other leg hasbeen heat sealed to the inside of the inner foil 4.

Each, handle member l4 hasa grip opening 16 formed therein.

If the paper sheet 5 does not extend up to the handle members 14 thewelds 15 can be through-going.

When the flattened bag shown in FIG. I is opened and the bottom isunfolded, the stiffening paper sheet contributes to giving the bag thesquare shape shown in FIG. 1, in that the edge portions 6,7 of the softfoils 3,4 located outside the paper sheet are easily folded around thelongitudinal edges 8,9 of the paper sheet while forming two end walls 17which thus connect the two opposite stiffened sidewalls 18. At theformation of the stiffened square bottom 19 two triangular foil portions20,21 indicated in FIG. 1 are formed between the bottom area and each ofthe end walls 17. These triangular'portions 20,21 are automaticallyfolded inwards towards each other to form a triangular pocket 22 (FIG.2) which contributes to an increased rigidity of adjacent end wall. Thevbag thus opened has itself in the same way as an empty paper bag.

lclaim:

l. A collapsible shopping bag having four sides and a square bottom whenopened out from a flattened state comprising two layers of flexible andheat sealing plastics foil, an intermediate stiffening sheet of Kraftpaper inserted between said layers extending continuously only acrosssaid bottom and along two opposite bag sides, said bag in flattenedstate com prising two side-forming walls connected by a transversebellows fold to form said square bottom, the mating longitudinal edgesof said walls and the ends of said bellows fold being closed by heatsealing of said plastic foil layers.

1. A collapsible shopping bag having four sides and a square bottom whenopened out from a flattened state comprising two layers of flexible andheat sealing plastics foil, an intermediate stiffening sheet of Kraftpaper inserted between said layers extending continuously only acrosssaid bottom and along two opposite bag sides, said bag in flattenedstate comprising two side-forming walls connected by a transversebellows fold to form said square bottom, the mating longitudinal edgesof said walls and the ends of said bellows fold being closed by heatsealing of said plastic foil layers.